Children who are delivered via cesarean section are much more likely to become obese as they age when compared to those who were delivered vaginally, according to new research from the New York University School of Medicine. The study incorporated data on more than 10,000 UK infants.
The research found that eleven-year-olds who were delivered by C-section were 83% more likely to be obese than their peers which were delivered vaginally, even after other risk factors were taken into account; factors such as their mother’s weight and how long the baby was breastfed.
With delivery by C-section, “there may be long-term consequences to children that we don’t know about,” said Dr. Jan Blustein, lead researcher of the new study.
C-sections have been increasing in recent years in the US, “leading to concerns about possible complications for mothers and babies. According to the Centers for Disease Control and Prevention, C-sections accounted for almost 1 in 3 births in 2010 – up from 1 in 5 in 1996.”
It’s important to note that the increased likelihood of becoming obese because of delivery by c-section isn’t that large, according to Blustein, so it isn’t research that will influence the use of C-sections for medical reasons. With regards to elective C-sections though, she says: “a woman who’s considering C-section electively should probably know about those risks.”
Here are some details on how the research was done:
The researchers analyzed data from babies born in Avon, UK in 1991 and 1992 who were followed through age 15. Just over 9% of the infants were delivered via C-section. On average, kids delivered by C-section were born slightly smaller – by less than two ounces – than those who went through vaginal birth.
Starting at six weeks of age, however, C-section babies were consistently heavier than vaginally-born infants at almost all check-ins. That link was especially strong among children born to overweight mothers. Across the whole study group of children, rates of overweight and obesity ranged from 31% at age three to 17% at ages seven and 15.
It’s currently unclear whether C-section’s themselves are the cause for increased weight gain. The speculation, though, is that it may be because of the differences in gut bacteria GBT have been observed between babies delivered vaginally and those delivered by C-section.
“Generally, the early colonization and establishment of the intestine with bacteria seems very important. Yet, much more work is needed before we can explain the mechanisms of the early bacterial colonization,” Teresa Ajslev, from the Institute of Preventive Medicine in Frederiksberg, Denmark, told Reuters in an interview.
The researchers state though that as of now the connection is tenuous — perhaps differences in bacteria are unrelated to the increased likelihood of obesity?
“The other possibilities are (that) these are children that would have been heavier anyway,” Blustein said.
“Being heavy as a woman is a risk factor for C-section, so that’s the problem with trying to figure out whether this is real or if it’s simply a matter of selection.”
The new research was published in the International Journal of Obesity.